Several new HIV prevention interventions have proven to be highly effective at reducing transmission of HIV and have offered hope for containing and possibly reversing epidemics in sub-Saharan Africa. Modeling studies suggest that investment in rapid, coordinated scale-up of a combination of evidence-based HIV prevention interventions, including HIV testing and counseling (HTC), male circumcision (MC), antiretroviral therapy (ART) and prevention of mother-to-child transmission (PMTCT), can significantly reduce population-level HIV incidence and may be cost-effective. Rigorous evidence-based outcomes to support these projections of population-level impact are needed if national and international bodies are to justify further investment in combination prevention strategies. The primary objective of this funding is to complete an ongoing evaluation of the impact of a combination prevention package on population-level HIV incidence in Botswana and estimate the cost per HIV infection averted. The over-arching study design is a pair-matched Community Randomized Trial with an intervention arm that receives the combination prevention package and a control arm that receives standard of care with clinical, laboratory, and data management strengthening. A baseline household survey of approximately 20% of randomly selected households in each community is implemented to (1) establish an HIV incidence cohort and (2) estimate baseline and annual coverage of the combination prevention package. Individuals who enroll in the baseline household survey are followed annually to assess uptake of study services in both study arms and describe major outcomes. The HIV incidence cohort is followed annually to assess cumulative HIV incidence over 36 months, which is the primary study outcome of interest. An end-of-study survey targeting 100% of households in four community pairs (4 combination prevention communities and 4 enhanced care communities) will be used to estimate and compare combination prevention package uptake between arms. Additionally, laboratory research activities will be used to map genotypes from HIV-infected individuals identified during the study to inform viral genotype maps of enhanced care community and combination prevention community arms. Data regarding the magnitude of reduction in HIV incidence with the combination prevention intervention, if a reduction is observed, and the cost and cost-effectiveness of the intervention will provide key information for policy and program design about how to most effectively allocate limited resources to eliminate HIV transmission. The study will also provide valuable data about the feasibility and acceptability of scaling up a combination of biologically efficacious interventions to a level that will have impact. Finally, data from this study will be informative o sexual networks and risk groups and the most effective approaches to implementation in different settings, allowing for the design of more targeted treatment and prevention interventions for HIV.